The invention relates to increasing the breathability of a biodegradable polymer film.
It is desirable for films that are used in disposable applications including, e.g., personal hygiene, to be breathable and to exhibit good “hand,” i.e., softness. Breathability refers to the ability of moisture or water vapor to diffuse through a medium, e.g., a film or garment. The moisture vapor transmission rate of a film is generally related to the breathability of the film.
Various biodegradable polymers have been developed in an effort to enhance the disposal of waste generated by personal hygiene articles and disposable diapers in particular. These biodegradable polymers degrade under compost conditions into organic components such as carbon dioxide and water.
Some of these biodegradable polymers have high viscosity. As a result, it is difficult to process these biodegradable polymers under standard hot melt conditions and to coat thin films using these biodegradable polymers.